package net.studou.action;

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.util.Random;

import javax.imageio.ImageIO;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.apache.struts2.ServletActionContext;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;

import com.opensymphony.xwork2.ActionSupport;

@Component("codeAction")
public class CodeAction extends ActionSupport {

	private static final long serialVersionUID = -3504571803154758909L;

	public Logger log = LoggerFactory.getLogger(CodeAction.class);

	public String code() throws Exception {

		int width = 95;
		int height = 30;
		// 取得一个4位随机字母数字字符串
		String s = getCode();// 这个s的值就是页面验证码上显示的值

		// 保存入session,用于与用户的输入进行比较.
		// 注意比较完之后清除session.
		HttpSession session = ServletActionContext.getRequest().getSession();
		session.setAttribute("validateCode", s);

		HttpServletResponse response = ServletActionContext.getResponse();

		response.setContentType("images/jpeg");
		response.setHeader("Pragma", "No-cache");
		response.setHeader("Cache-Control", "no-cache");
		response.setDateHeader("Expires", 0);

		ServletOutputStream out = response.getOutputStream();
		BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
		Graphics g = image.getGraphics();
		// 设定背景色
		g.setColor(getRandColor(200, 250));
		g.fillRect(0, 0, width, height);

		// 设定字体
		Font mFont = new Font("Arial", Font.BOLD, 22);// 设置字体
		g.setFont(mFont);

		// 画边框
		// g.setColor(Color.BLACK);
		// g.drawRect(0, 0, width - 1, height - 1);

		// 随机产生干扰线，使图象中的认证码不易被其它程序探测到
		g.setColor(getRandColor(160, 200));
		// 生成随机类
		Random random = new Random();
		for (int i = 0; i < 155; i++) {
			int x2 = random.nextInt(width);
			int y2 = random.nextInt(height);
			int x3 = random.nextInt(12);
			int y3 = random.nextInt(12);
			g.drawLine(x2, y2, x2 + x3, y2 + y3);
		}

		// 将认证码显示到图象中
		g.setColor(new Color(20 + random.nextInt(110), 20 + random.nextInt(110), 20 + random.nextInt(110)));

		g.drawString(s, 4, 21);

		// 图象生效
		g.dispose();
		// 输出图象到页面
		ImageIO.write((BufferedImage) image, "JPEG", out);
		out.close();

		return null;

	}

	private Color getRandColor(int fc, int bc) { // 给定范围获得随机颜色
		Random random = new Random();
		if (fc > 255)
			fc = 255;
		if (bc > 255)
			bc = 255;
		int r = fc + random.nextInt(bc - fc);
		int g = fc + random.nextInt(bc - fc);
		int b = fc + random.nextInt(bc - fc);
		return new Color(r, g, b);
	}

	private String getCode() {
		String code = "";

		String[] s = new String[] { "A", "B", "C", "D", "E", "F", "G", "H", "G", "K", "L", "M", "N", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z", "2", "3", "4", "5", "6", "7", "8", "9" };
		Random r = new Random();
		for (int i = 0; i < 5; i++) {
			code = code + s[r.nextInt(s.length - 1)];
		}

		return code;
	}

	public static void main(String[] args) {
		System.out.println(new CodeAction().getCode());
	}

}
